ISOLATION, MORPHOLOGICAL IDENTIFICATION AND EVALUATION OF CADMIUM TOLERANCE OF FUNGI FROM COCOA CROPS
MARIO ALCARRAZ CURI
*
Laboratory of Industrial Bioprocesses, Faculty of Biological Sciences, National University of San Marcos, Lima, Peru
ANA MARIA EVANGELIO GUTIERREZ
Laboratory of Industrial Bioprocesses, Faculty of Biological Sciences, National University of San Marcos, Lima, Peru
MC. KENNET YAMEL ENRIQUEZ MONTESINOS
Laboratory of Industrial Bioprocesses, Faculty of Biological Sciences, National University of San Marcos, Lima, Peru
JEAN PAUL JULIAN IBARRA
Laboratory of Industrial Bioprocesses, Faculty of Biological Sciences, National University of San Marcos, Lima, Peru
JOSELIN WENDY PALOMO ATANACIO
Laboratory of Industrial Bioprocesses, Faculty of Biological Sciences, National University of San Marcos, Lima, Peru
DEYSI DAMINA RENDON GODOY
Laboratory of Industrial Bioprocesses, Faculty of Biological Sciences, National University of San Marcos, Lima, Peru
ANDRES STEFANO SANCHEZ MANRIQUE
Laboratory of Industrial Bioprocesses, Faculty of Biological Sciences, National University of San Marcos, Lima, Peru
*Author to whom correspondence should be addressed.
Abstract
The objective of the present study was to evaluate cadmium resistance of fungi isolated from cocoa fields in order to apply them for cadmium bioremediation in cocoa plantations. The analyzed soil samples came from the cocoa areas of Junín, Pucallpa and Mazamari, Peru. The fungi were isolated on potato dextrose agar (PDA) and identified by their appearance from the colony. Subsequently, all the isolated strains were cultured on PDA with 87.64 ppm of cadmium to rule out the non-resistant or poorly resistant ones. Positive strains were identified by their macroscopic and microscopic morphology. Cadmium tolerance was calculated by measuring the diameter of the colony formed on PDA with 87.64, 175.29 and 350.59 ppm of cadmium. A total of 100 fungal strains were isolated, of which 24 had tolerance to 87.64 ppm, 21 to 175.29 ppm and 16 to 350.59 ppm. The fungi with the highest tolerance were J2E2 (Acremonium sp.), MP4H1 (Curvularia sp.), HK6 (Not Described, ND) and JH3 (Fusarium sp.) respectively. Likewise, the strains with the best tolerance indices were HK6 (ND), H2 (Penicillium sp.), AP3H4 (ND) and J2E2 (Acremonium sp.). The research allows us to conclude that the native fungi isolated from cocoa soils show tolerance to high concentrations of cadmium, therefore they have the potential to be used as bioremediators in cocoa plantations or in other biotechnological processes.
Keywords: Isolation, cadmium, tolerance, Fungi, soils and cocoa